Coastal Hazards: Management and Climate Change Implications
摘要
The 7500 km long coastline of India has varying geomorphological, sedimentological, and hydrodynamical characteristics, and this vast coastal zone is exposed to different coastal hazards. The important coastal hazards of relevance for the Indian coast are monsoonal waves, surges, beach erosion, tsunami, and sea level rise. This chapter dwells on each of these hazards, the extent of their impact, and possible options for their management with particular reference to the climate change scenario. The erosion due to monsoonal waves is normally a seasonal one unless episodic events like cyclones hamper the recovery of beach in the post-monsoon period. However, as per the latest assessments available, about 34% of coastline of the country is under erosion which is mainly attributed to anthropogenic factors. About three-fourths of the Indian coastline is vulnerable to tropical cyclone and the resulting storm surge. The December 2004 tsunami generated by the M9.3 Sumatra-Andaman earthquake has added another dimension to the coastal hazard vulnerability of the Indian coast with Makran remaining as another potential tsunamigenic source for the west coast of India. There are different options for coastal hazard management which has to be site-specific based on the hazard vulnerability, coastal geomorphic setup, and environmental impact. Coastal hazard management projects, in addition to the present-day approach of protecting life and property, must address livelihood security of coastal communities, recreational requirements, coastal tourism, and conservation of ecosystems. The management of coastal hazards is going to be a tough task in the coming decades due to climate change. Measures for climate change resilience need to be in-built in the coastal hazard management programs.